Process of concentrating ores.



J. M. OALLOW.

PROCESS OF OONGENTRATING omss.

APPLICATION FILED APRJO, 1914.

1,m5,897. Patented Jan.19,1915.

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JOHN M. CALLOW, OF SALT LAKE CITY, UTAH, ASSIGNOR TO METALS RECOVERY COM- PANY, OF AUGUSTA, MAINE, A CORPORATION OF MAINE.

PROCESS OF GONCENTRATING ORES.

Specification of Letters Patent.

Patented Jan. 19, 1915.

Application filed April 10, 1914. Serial No. 831,050.

To all whom it may concern:

Be it known that I, JOHN M. CALLow, a subject of the King of Great Britain, residing at Salt Lake City, in the county of Salt Lake and State of Utah, have invented certain new and useful Improvements in Processes of Concentrating Ores, of which the following is a specification.

My invention relates to a new and useful process of concentrating metallic ores by separating the valuable metallic particles from the barren or rocky constituents thereof.

The invention more specifically is related to a process which is distinguished from the usual amalgamation processes in which the ore forms an amalgam and it is identified more particularly with what is known as the flotation process, wherein a certain percentage of oil, or of two dissimilar oils, or an oil and an acid, or an oil and an alkali is mixed with finely ground ore pulp and the mixture is then subjected to a violent agitation either by mechanical propellers or by a fluid admitted under pressure. The result is that large quantities of air are beaten into or impregnated with the pulp, which action produces a froth composed of bubbles of air and oil to which the mineral particles attach. This froth has the appearance of an aggregation or mass of fine small soap bubbles,

which when collected, and the froth discharged, or broken down, displaces the mineral particles that have been caught.

The secret of successful flotation of ore particles aside from the proper percentage of oil or other reagent is the beating or delivering of large volumes of air into the pulp, because in the absence of air no froth will be formed. Ordinarily to obtain the desired aeration of the pulp, mechanical stirrers, or propellers have been used and are in more or less general practice in this art.

In a prior application filed by me on October 6, 1913, Serial Number 7 93,695, I have disclosed and claimed a means for agitating and aerating the pulp and wherein no mechanical stirrers are used, the improved means consisting in the employment of compressed air which is introduced into the pulp from beneath through some porous body, and in innumerable fine streams or jets. The compressed air thus becomes the medium of (1) fully aerating or charging the pulp with the desired volume of air and (2), it likewise induces and maintains that agitation of the pulp which heretofore was obtained by the mechanical propellers or stirrers before alluded to.

The porous medium referred to is described in my said prior application as be' -of porous wood, such as bass-wood, or in fact any porous material through which air can be forced in more or lessirregular jets of infinite number and fineness. The character of the porous material employed is,

therefore, unimportant, except that it shall,

have the property of permitting the air introdced into the tank to be discharged through the pores of the material through- .out substantially the entire surface thereof and into the body of pulp in the chamber above with the result that immediately upon the introduction of the air a violent agita:

tion or ebullition takes place, and froth is observed to rise and form on the surfaceof the pulp contents, which greatly increases in volume and density as the action proceeds.

Although I have referred to a particular means for agitating and aerating the fluid contents, the present invention is not restricted to any such means and may be successfully used where the agitation of the pulp is effected by other means, as propellers or stirrers or in fact by any device or combination of devices which will produce or assist the formation of the foam or froth in a pulp or solution containing powdered ores and water and a percentage of oily substance having a preferential afiiinity for metalliferous matter over gangue in the pulp, since the present improvement in the art relates more particularly to a process for removing, discharging and breaking down by the aid of a vacuum, or suction, the foam,

ioo

froth or sud which, rises to and accumulates 7 suitable construction and dimensions and the porous medium and directly into the pulp in the form of more or less irregular jets of infinite number and fineness, and the jets being under pressure, their admission 5 into the body of pulp results in a violent agitation and ebullition of the pulp contents. This induces the froth, foam or sud to generate and to rise and form on the surface of the pulp contents, the froth or foam increasze ing in volume and density as the action proceeds. In order that this foam, froth or sud may be discharged and broken down and the mineral particles adhering to the bubbles displaced and recovered, I locate over and in 2'5 proximity to the upper surface of the body of froth, foam or sud, the mouth of a suitable nozzle, E, which in turn is connected to a pipe leading to a tank, F, of any suitable character and which tank has connected to it the suction end of an exhaust fan, G, or

other vacuum producing means, whereby upon the operation of the fan, or other device, a vacuum is created in the tank, F, sufficient to cause the mass of air bubbles with the adhering mineral particles to be broken down or collapsed and drawn into the open mouth of thenozzle and delivered into the vacuum tank, This action will be readily understood when it is suggested that 40 under the ordinary conditions of operation the bubbles are ruptured by the expansion of the contained air on reaching the surface or coming under the influence of the vacuum, where the external pressure is less than that within the bubbles.

In order to prevent a short'circuiting of current induced by the exhaust fan the tank, F, may be provided with ai' baflie or partition, and-this insures thefiuid and mineral particles carried along by the suction being deposited in the tank.

The tank may have any suitable valve controlled means at the bottom, and the dis charge of the material from the tank, F,

may be intermittent, through the agency of an appropriately operated valve, I, or equivalent means, or the discharge may be continuous by extending the end of the discharge pipe-and utilizing this as a draft tube having it's lower end dipping into an appro- 1pirl'liate waterseal, J, as indicated by dotted From the foregoing it will be readily understoodthat the essential feature of the present invention is a process which includes as a stepthe removal and breaking down of -the air bubbles, froth,'foam or sud, in a buoyant or frothing process, by means of a. vacuum or suction applied to the surfaceof or adjacent the up, er surface of the mass of accumulating bub les and conducting the fluid contents of the bubbles and the mineral particles into a suitable receiver or tank from which 'they'may be removed for subsequent treatment in any desired manner. I

Having .thus described my invention, what I claim as new and desire to secure by Let ters Patent is 1. The process herein described of breaking down and discharging the froth, foam or sud, accumulating on the surface of an aerated and agitated mineral-bearing pulp containing a frothable agent having a selective affinity for metalliferous particles, said process consisting, essentially, in pro ducing in a vessel open to the atmosphere a difference in pressures between the inside and outside of the air bubbles forming the froth, foam or sud, and conducting the fluid contents of the broken down bubbles '9 and mineral particles thereof to a receiver.

2. The process herein described of break- I ing down and discharging the froth, foam or sud, accumulating on the surface of an aerated and agitated mineral-bearing pulp containin a frothable agent having a selective a nity for metalliferous particles,

said process consisting, essentially, in applying a suction to the surface of the froth, foam or sud in a vessel open to the atmos- 19g phere and utilizing the suction as a carrier for the fluid contents and mineral particles of the disrupted air bubbles.

3. In a buoyant process wherein a froth, foam or sud is produced by agitating and aerating a mineral-bearing pulp containing a frothable agent having a selective aflimty for metalliferous particles over the gangue in the pulp, the step of inducing a suction in proximity to the surface of the froth, foam or sud produced in a vessel open to the atmosphere for the purpose of breaking down the air bubbles and discharging the mineral particles carried thereby. 4. The process herein described, which consists in agitating and aerating by means of a fluid under pressure in a vessel open to the atmosphere, a mineral bearing pulp containin a frothable agent having a selective a nity for the mineral over the 20 gangue-constituents of the pulp and thereby producing a froth, foam or sud which rises and accumulates on the surface of the pulp, and then applying a suction 1n proximity to the surface of the froth, foam or sud, for the purpose of breaking down the air bubbles and discharging the fluid contents thereof and the contained mineral particles. I

5. The process herein described of break- 1:30

- ing down and discharging the froth, foam inv described, .Which consists, essentially, in

or sud accumulating on the urface of an aerated and agitated mineral-bearing pulp aerating and agitating a mixture of comminutedi ore and water and a frothable agent in a vessel open to the atmosphere and thereby generating a foam, froth or -sud which rises to the surface of the liquid contents of the mixture, and while the froth,

foam or. sud is in substantially. quiescent condition, pneumatically breaking down the air bubbles and simultaneously conveying the ore particles floated thereby to a closed recelver.

-7. In apparatus for separting the metalliferous from the non-metalliferous ingredicuts of an ore mass, the combination of a pulp receptacle, means for forcing substantially uniformly distributed bubbles to the surface of said mass, and independent means for exhausting said bubbles from 8. In apparatus for separating the metal- 1ifero1'1s from the non-metalliferous ingredifents of; an ore mass, the combination of a pulp receptacle, means for-forcing substan the upper tially uniformly distributed bubbles 'to the surface of said mass, and independent pne'umatic means for breaking down the bubbles and simultaneously carrying off the mineral particles floated therehy.",'

9. The process herein described of breaking down and, discharging the froth, foam or sud, accumulating on the surface-ofa mineral-bearing pulp containing a froth producing agent having a selective afiinity for metalliferous particles, said process consisting, essentially, in producing a difference in pressures between the inside and outside of the bubbles forming the froth,

- foam or sud, and conducting the fluid contents of the broken down bubbles and mineral particles thereof to a receiver.

10. The process herein described, of breaking down and discharging the froth, foam or sud, accumulating on the surface of a mineral -.bearing pulp containing a froth producing agent havin a selective aflinity for metalliferous partic es, said process consisting, essentially, in applying a suction to the surface of the froth, foam or sud, and utilizing the suction as a carrier for the fluid contents and mineral particles of the disrupted air bubbles.

In testimony whereof I affix my signature in presence of two witnesses.

JOHN M. OALLOW. Witnesses:

J N0. J. MEANY, FRANK H. BLACK. 

